Wind turbines use naturally-available wind energy to generate electrical power in an environmentally-friendly manner. Wind turbine plants and other forms of renewable power generation connected to provide electrical power to a power grid can be susceptible to so called “weak-grid” conditions. U.S. patent application Ser. No. 13/550,699, United States patent application publication number US 2014/0021720 A1, commonly assigned to the assignee of the present invention and incorporated by reference herein, describes use of a technique for controlling a power generation system, such as involving a wind power plant, where the control technique involves injection of reactive power into the system.